Concentration of ores



Patented May 15, 1945 CONCENTRATION OF ORES Arthur H. Fischer, New York, N. Y., assignor to Minerec Corporation, New York, N. Y., a corporation of New York No Drawing. Application September 21, 1943,

Serial No. 504,068' 3 A 12 Claims. (c1. 209-166) This invention relates to the concentration of ores and has for an object the provision or certain improvements in concentration operations. More particularly, the invention contemplates the provision of certain improvements in flotation operations. tion is to provide certain improvements in flota tion methods or processes. Another object of the invention is to provide new and improvedflotation reagents and methods of producing such reagents.

The invention is based on my discovery that carbonyl tetrathio diphosphates are effective A further object of the invenflotatio reagents which may be employed a'dvantageously as mineral collecting agents in conjunction with frothing agents and conditioning agents in froth flotation operations.

. The reagents of the invention may be produced by reacting dithiophosphoric acids and salts of the acids with phosgene (carbonyl chloride, COClz) in accordance with the following When substitution-products of .dithiophosphoric acids or salts of such acids containing organic radicals are. employed, carbonyl tetrathio diphosphates containing corresponding organic radicals will be produced. Substitution-products of acids and salts containing alkyl radicals or aryl radicals or both may be employed, and, in the above formulae, R- represents such radicals.

The use of ell-substituted organic compounds results in the production of tetra-substituted compounds, the use of di-substituted esters, for example, results in the production of tetra esters of carbonyl tetrathio disphosphate.

Among the compounds found most suitable for use in flotation concentration processes are (1) Tetraethyl carbonyl tetrathio disphosphate,

(2) Tetrabutyl carbonyl tetrathio disphosphate,

and

(3) Tetracresyl carbonyl tetrathio diphosphate.

(Compounds of the invention and their methods of production are described and claimed in my copending application Serial No. 504,067, filed September 27, 1943.)

The following example illustrates a method oi preparing compounds in accordance with my invention:

153 grams of pure ammonium dethyl dithiophosphate were suspended, with stirring, in 600 c. c. of ether, and 45 grams of phosgene of theoretical) were passed into the suspension as rapidly as possible. The temperature of the suspension was maintained at about 0 C. The reaction was complete a few minutes after all of the phosgene had been added. Water was added todissolve the ammoniumchloride produced during the course of the reaction, and the water and ether phases were separated. The

ether phase was heated under reduced pressure 4 remove the ether, and a residual water-insoluble oily product was obtained.

The oily product was substantially pure tetraethyl carbonyl tetrathio disphosphate, as indicated by the following data:

The yield was 149.5 grams. Theoretical yield based on carbonyl compound is 149.8 grams.

By analysis I Theoretical Per cent sulphur 32. 67 32. 18 Per cent phosphorus 15. 51 15. 55

Carbonyl tetrathio diphosphates containing other organic radicals may be produced by the same procedure or by similar procedures when employing organic dithiophosphates containing such other organic radicals.

When employed as flotation reagents, carbonyl tetrathio diphosphates may be pur or substantially pure or theymay be mixed with other organic thio compounds in reaction products 'resulting from processes employed in their production. The pure compounds may be produced cy employing pure reagents and carrying out the reactions at low temperatures. At relatively nigh temperatures, such as room temperature, side reactions take place which result in the production of reaction mixtures containing the carbonyl tetrathio diphosphates and other organic thio compounds. The use of impure reagents in the production of the carbonyl compounds also results in the production of relatively impure or crude reaction mixtures. The yield of carbonyl compound in any particular reaction will depend upon the purity of the reagents and the temperature employed. The purity of reagents and the temperatures employed in producing flotation reagents of the invention v designed for the concentration of sulphide ores.

The following examples illustrate the advantages of the reagents of the invention over reagents employed heretofore:

Example I Utah Copper Company copper sulphide ore products of the following compositions with respect to copper and iron were ground in water to form four separate aqueous pulps which were subjected to separate froth flotation operations in the presence of the reagents indicated with the production of tailing products of the analysis indicated:

concentrates and tailings of the analyses shown:

Test No.

Concentrate: per cent Zn 36.7 36.3

Tails: per cent Zn O. 31 0.14

REAGENTS (POUNDS PER TON) line 1.50 1. 50 Copper sulphate 30 30 Acre 25 05 05 Standard reagent. 16 Tetraethyl carbonyl tetrathio diphosphate 135 Test No.

Ore:

Per cent Cu 950 950 l. 145 l. 145 Per cent Fem. 2. 60 2. 60 2. 95 2. 95 Tails:

PercentCu .060 .040 .080 .075 Per cent Fe. 2.00 2. 00 2.45 2. 50

REAGENTS (POUNDS PER TON) Lime 3. 25 3. 25 3. 75 3. 75 Cyanide 015 015 .015 015 Cresylic acid 33 33 33 33 Standard reagent .034 .034 Tetfiactgesyl carbonyl tetrathio diphos- 04 p a Tetracthyl carbonyl tetrathio diphosphate 02 Example II Example III Two separate quantities of a zinc sulphide one in the form of aqueous pulps were subjected to froth flotation operation in the presence of the OR OR OR in which R represents an organic radical.

2. The method of concentrating sulphide ore which comprises subjecting the ore in-the form of a pulp to a froth flotation operation in the presence of a compound having the following structural formula:

on on 0a 0a g H II in which R represents an alkyl radical.

3. The method of concentrating sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of a compound having the following structural formula:

u l S t s in which R represents an aryl radical.

4. The method of concentrating sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of a compound having-the following structural formula:

OR OR OR g II o in which R represents an ethyl radical.

5. The method of concentrating sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of a compound having the following structural formula:

OR OR on tilt! in which R represents a butyl radical.

reagents indicated below with the production =zo'f 76 6. The method of concentrating sulphide ore which comprises subjecting the ore in the form of a pulp to a froth' flotation operation; in the presence of a compound structural formula: I on /OR on r 1? s 0 s in which It represents a cresyl radical. Y

7. The method of concentrating sulphide ore which comprises subjecting the ore in the form of 'a pulp to a froth flotation operation in the presence of the reaction product of .a dithiophosphate and phosgene comprising a compound haying the following structural formula:

in which R represents an organic radical.

v 8. The method of concentrating sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operationinthe presence of the reaction product of'a dithiophosphate and phosgene comprising a compound having the following structural formula:

in which R represents an alkyl radical.

9. The method of concentrating sulphide ore which comprises subjecting the ore inthe form of a pulp to a froth flotation operation in the presence of the reaction product of a dithiophosphate and phosgene comprising a compound having the following structural formula:

having the following OR. OR OR OR .i t i in which R represents an aryl radical.

10. The method of concentrating sulphide ore vwhich comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of the reaction product of a dithiophosphatev and phosgene comprising a compound having the following structural formula:

0R on on on t a i in which R represents an ethyl radical.

11. The method of concentrating sulphide ore which comprises subjecting the ore in the form of a pulp to a froth flotation operation in the presence of the reaction product of a dithiophosphate and phosgene comprising a compound having the following structural formula:

in which R represents a cresyl radical. v

a ARTHUR H. FISCHER. 

